I 88 TEETH OF AARD VARK CHAP. Thomas1 there are seven milk teeth on each side of the upper jaw (limited to the maxillae, and thus not incisors). An eighth tooth was discovered on one side of one of the specimens examined by Thomas. In the lower jaw there are only four milk teeth on each side. It is interesting to note that the histological structure FIG. 308.—Section of lower jaw witli tlie teeth, of Orycteropus. x 2. (After Owen.) of these milk teeth agrees with that of the permanent teeth. There are two species of this genus found in Africa : the southern, 0. capensis, is more hairy than the northern, 0. aethiogicus. Q. gaudryi is a Pliocene species from the Island of Sainos and from Persia, described by Dr. Forsyth Major and Dr. Andrews.2 It closely resembles the existing O. aetJiiopicus. Of the Scaly Anteaters, Group SQUAMATA or Manidae, there is really but one genus, though Phatagin, JPholidotus, Smutsia, and Pangolin have been used to distinguish various forms. The genus Manis is African and Oriental in range. Dr. Jentiiik, who has lately revised the species, allows seven.3 The external form of these animals is fairly well known, the remarkable scales dis- tinguishing the Pangolins from other animals. Between the scales lie hairs, which seem to be absent in the adults of the African species, though present in the young, thus affording a convenient method of distinguishing the Ethiopian from the Oriental forms. The scales have been compared to agglutinated hairs. That they are not " merely mimetic of the Lizards* scales " is held by Weber,4 who compares them directly with those struc- 1 Proc. Roy. Soc. xIviL 1890, p. 246. 3 Proc. Zool. Sfoc. 1893, p. 239, and 1896, p. 296. a "Revision of the Manidae in the Leyden Museum," JVoies Leyd. M-its. iv. 1882, p. 193. * Weber, Zool. Mrgebnisse eincr Jl&ise in Nicderl. Ost Indirn, 1892. See also Homer, in Jen. Zeitsthr. xxxl. 1896, p. 604, and Reh, ibid. xxx. 1895, p. 137.